The present invention relates to a communication system, a communication device, a vehicle and a communication method and, in particular, relates to the communication system, the communication device, the vehicle and the communication method that are favorably utilized in an on-vehicle communication machine (or an on-vehicle communication equipment), a vehicle that loads the on-vehicle communication machine (or the on-vehicle communication equipment) thereon, a roadside communication machine (or a roadside communication equipment) and so forth that configure an intelligent transport system (ITS).
As a network of vehicles evolves, it becomes unavoidable to connect each vehicle with the outside over a network. Various applications of the network of vehicles are examined and a range of applications of the network of vehicles covers various fields. Therefore, it becomes an important task to prevent illegal access at a gateway that serves as an inlet into a communication path. Therefore, the security of a level that is as high as that of a firewall system and so forth of the type that is performed in a personal computer (PC), related-art IT (Information Technology) system and so forth over Internet is demanded.
In Japanese Unexamined Patent Application Publication No. 2011-229184, there is disclosed a communication system that a network connection service that a host device and a management computer give a dynamic IP (Internet Protocol) address to a communication module provides. It is possible to make it difficult to directly access to a computer that is present on an internal network from the outside by converting the IP address depending on whether it is used on the internal network or an external network.
In Japanese Unexamined Patent Publication No. 2002-176444, there is disclosed a position-information-based communication address allocation method by which it is possible to specify an area of an information transmission source by giving locality to a communication address. When acquiring the IP address, an information processing device sets installation position information of the IP address and an IP address management server generates the IP address that information indicating the area such as a zip code, a telephone number and so forth is included in a predetermined number of bits on the basis of the installation position information and gives the IP address so generated to the information processing device.